Researchers: The symmetrons needed to explain dark energy were not found

One of the candidates for ‘dark energy’ is the symmetron field. Researchers have developed an experiment capable of measuring extremely small forces with the help of neutrons. The measurements could have provided pointers to the mysterious symmetrons, but the particles didn’t show up. This excludes the possibility of symmetrons in a broad parameter range. ‘Dark energy’ is going to have to be explained differently.

One thing is certain: there’s something out there we don’t yet know. For years now scientists have been looking for “dark matter” or “dark energy” — with our current inventory of particles and forces in nature we just can’t explain major cosmological phenomena, such as why the universe is expanding at an ever faster rate.

mirror used to measure neutrons/TU, Wien

New theories for “dark energy” have been suggested. One of the candidates is the so-called “symmetron field,” which is said to pervade space much like the Higgs field. At the TU Vienna researchers have developed an experiment capable of measuring extremely small forces with the help of neutrons. The measurements were taken during a 100-day campaign at the Institut Laue-Langevin, on its PF2 ultra-cold neutron source. They could have provided pointers to the mysterious symmetrons — but the particles didn’t show up. Although this is not the end of the theory, it does at least exclude the possibility of symmetrons existing across a broad range of parameters — and “dark energy” is going to have to be explained differently. Paper.(open access) – Gunther Cronenberg, Philippe Brax, Hanno Filter, Peter Geltenbort, Tobias Jenke, Guillaume Pignol, Mario Pitschmann, Martin Thalhammer, Hartmut Abele. Acoustic Rabi oscillations between gravitational quantum states and impact on symmetron dark energy. Nature Physics, 2018; DOI: 10.1038/s41567-018-0205-x More.

Are we sure about rapidly increasing cosmic inflation? See, for example: Cosmic inflation theory loses hangups about the scientific method

Science at sunset: Dark energy might make a multiverse hospitable to life… if it exists

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Researcher: The search for dark matter has become a “quagmire of confirmation bias” So many research areas in science today are hitting hard barriers that it is reasonable to think that we are missing something.